Fiber mat for battery plate reinforcement

Abstract

Embodiments of the invention provide batteries, electrodes, and methods of making the same. According to one embodiment, a battery may include a positive plate having a grid pasted with a lead oxide material, a negative plate having a grid pasted with a lead based material, a separator separating the positive plate and the negative plate, and an electrolyte. A nonwoven glass mat may be in contact with a surface of either or both the positive plate or the negative plate to reinforce the plate. The nonwoven glass mat may include a plurality of first coarse fibers having fiber diameters between about 6 μm and 11 μm and a plurality of second coarse fibers having fiber diameters between about 10 μm and 20 μm.

What is claimed is: 
     
       1. A plate or electrode for a lead-acid battery comprising:
 a grid of lead alloy material; 
 a paste of an active material applied to the grid of lead alloy material; and 
 a nonwoven fiber mat disposed on a surface of the paste of the active material, wherein the nonwoven fiber mat comprises a tensile strength in a machine direction of at least 22 lbs/3 inch and a tensile strength of at least 13 lbs/3 inch in a cross-machine direction, wherein the nonwoven fiber mat comprises a mat thickness of between about 0.006 inches and 0.008 inches, and wherein the fibers of the nonwoven fiber mat are composed entirely of a blend of coarse glass fibers having average fiber diameters of between 6 μm and 20 μm including: 
 a plurality of first coarse glass fibers having fiber diameters between 6 μm and 11 μm; and 
 a plurality of second coarse glass fibers having fiber diameters between 13 μm and 20 μm; 
 wherein the nonwoven fiber mat comprises between about 25% and 75% of the first coarse glass fibers and between 25% and 75% of the second coarse glass fibers. 
 
     
     
       2. The plate or electrode of  claim 1 , wherein the first and second coarse fibers comprise fiber lengths between about ⅓ inch and about 1½ inch. 
     
     
       3. The plate or electrode of  claim 2 , wherein the first and second coarse fibers comprise fiber lengths between about ½ inch and about ¾inch. 
     
     
       4. The plate or electrode of  claim 1 , wherein at least one of the first coarse fibers or the second coarse fibers comprise fibers having a fiber length of at least ⅓ inch. 
     
     
       5. The plate or electrode of  claim 4 , wherein at least one of the first coarse fibers or the second coarse fibers comprise fibers having a fiber length of at least ½ inch. 
     
     
       6. The plate or electrode of  claim 1 , wherein the nonwoven fiber mat comprises about 50% of the first coarse fibers and about 50% of the second coarse fibers. 
     
     
       7. The plate or electrode of  claim 1 , wherein the paste of the active material penetrates into the nonwoven fiber mat between about 0.001 inches and about 0.020 inches from the surface of the paste or plate. 
     
     
       8. The plate or electrode of  claim 1 , wherein an additional nonwoven fiber mat is disposed on an opposite surface of the paste of the active material so that the paste of the active material and the electrode are disposed between two nonwoven fiber mats. 
     
     
       9. The plate or electrode of  claim 8 , wherein the two nonwoven fiber mats comprise opposite sides of a bag that encloses or envelopes the paste of the active material and the electrode. 
     
     
       10. The plate or electrode of  claim 1 , wherein the nonwoven fiber mat further comprises a binder applied to the mat between about 10% and 45% by weight of the mat. 
     
     
       11. The plate or electrode of  claim 10 , wherein the binder is applied to the mat between about 20% and 30% by weight of the mat.